What is the ruling on a husband swearing that he will not enter the home for a week and considering himself outside the religion of Muhammad, peace and blessings be upon him, if his wife mentions her desire to go anywhere with his friend's wife, knowing that they both regret it?

It is not permissible for a man to swear an oath upon himself involving curses, wrath, or apostasy and abandoning the faith, due to the threat and warning it contains. Jurists have differed regarding the necessity of expiation (kaffarah) when breaking such forbidden oaths. The more cautious approach is to perform expiation.

If the husband swore that he would not enter the house for a week unless you became an infidel if you went out with your neighbor, this is a forbidden oath. He must repent and feel remorse. If he sees good in your going out with your neighbor, he should expiate his oath, based on the Prophet's (peace be upon him) saying: "Whoever swears an oath and then sees something better than it, let him do that which is better and expiate his oath."